on 17 jan 2012 sales order no (1000)raised for rs 5,000,00
advance payment received on 20 jan 2012 rs 2,000,00
validity of the sales order(1000) is on 30 jan 2012
on 21 delivery is to be taken for rs 3,000,00- sys should through error because advance payment is for rs 2,000,00-
so delivery quantity should be changed to rs 2,000,00 so system should accept the delivery